Drop down platforms for swimmers, divers and for tender vessels are known, as described in patents DE 196 02 331, U.S. Pat. No. 6,327,992, U.S. Pat. No. 5,690,045, enabling persons or material to be lowered comfortably into the water or to be taken on board.
Surface piercing drives, which have a relatively long propeller shaft placed just under the waterline behind the transom of the watercraft, is for example a drop down swim platform only possible with an electric or hydraulically activated horizontal sliding of the platform, which then can be lowered behind the propeller